From sounds to lexical representations

Average English-native 20-year-old knows ~42,000 words: mental lexicon

Lexical development:

• Vocabulary size (Braginsky et al. 2019)
• Semantic and phonological associations (Fourtassi, Bian, and Frank 2020)
• Efficiency in lexical access (Marchman and Fernald 2008)

From sounds to lexical representations

From sounds to lexical representations

Vocabulary growth

Vocabulary size grows non-linearly during the second year of life

Figure 1: Vocabulary size norms for 51,800 monolingual children learning 35 distinct languages (wordbank)

Early dynamics of lexical processing

Challenges of a bilingual environment

• Increased complexity in linguistic context (learning two codes)
• Reduced linguistic input (split into two languages)
• Increased referential ambiguity
• Bilinguals keep up with monolinguals (Sebastian-Galles and Santolin 2020)

Challenges of a bilingual environment

Bilinguals acquire words at similar rates as monolinguals (Hoff et al. 2012)

A cognate facilitation in lexical acquisition?

Lexically closer languages ➡️ Larger vocabulary size (Floccia et al. 2018)

English-Dutch > English-Mandarin

Cognates acquired earlier than non-cognates (Mitchell, Tsui, and Byers-Heinlein 2023; Bosch and Ramon-Casas 2014)

A cognate facilitation in lexical acquisition?

Figure 2: Pairwise lexical similarity (average Levensthein similarity across translations).

A cognate facilitation in lexical acquisition?

Introduction

• Bilinguals keep up with monolinguals in vocabulary growth
• The presence of cognates seems to facilitate vocabulary acquisition
• Language co-activation has been suggested to underlie this phenomenon
• Mechanisms supporting the role of co-activation in cognate acquisition are unclear

Language non-selectivity

Language non-selectivity

Language non-selectivity

The AMBLA model

\[ \begin{aligned} \definecolor{myred}{RGB}{ 168, 0, 53 } \definecolor{myblue}{RGB}{ 0, 64, 168 } \definecolor{mygreen}{RGB}{0, 168, 87} \definecolor{grey}{RGB}{128, 128, 128} \textbf{For participant } &i \textbf{ and word-form } j \text{ (translation of } j'): \\ {\color{mygreen}\text{Age of Acquisition}_{ij}} &= \{\text{Age}_i \mid {\color{myred}\text{Learning instances}_{ij}} = {\color{myblue}c} \}\\ \color{myred}{\text{Learning instances}_{ij}} &= \text{Age}_i \cdot \text{Freq}_j \\ \textbf{where:} \\ {\color{myblue}c} &= 300 \\ \text{Freq}_j &\sim \text{Poisson}(\lambda = 50) \end{aligned} \]

Extended to the bilingual case:

Accumulation of learning instances, a function of Exposure and Frequency.

\[ \begin{aligned} \definecolor{myred}{RGB}{ 168, 0, 53 } \definecolor{myblue}{RGB}{ 0, 64, 168 } \definecolor{mygreen}{RGB}{0, 168, 87} \definecolor{myorange}{RGB}{ 235, 127, 26 } \textbf{For participant } &i \textbf{ and word-form } j \text{ (translation of } j'): \\ \text{Age of Acquisition}_{ij} &= \{\text{Age}_i \mid \text{Learning instances}_{ij} = c \}\\ \text{Learning instances}_{ij} &= \text{Age}_i \cdot \text{Freq}_j \cdot {\color{myred}\text{Exposure}_{ij}}\\ \textbf{where:} \\ c &= 300 \\ \text{Freq}_j &\sim \text{Poisson}(\lambda = 50) \end{aligned} \]

Implementing a cognateness facilitation mechanism:

\[ \begin{aligned} \definecolor{myred}{RGB}{ 168, 0, 53 } \definecolor{myblue}{RGB}{ 0, 64, 168 } \definecolor{mygreen}{RGB}{0, 168, 87} \definecolor{myorange}{RGB}{ 235, 127, 26 } \textbf{For participant } &i \textbf{ and word-form } j \text{ (translation of } j'): \\ \text{Age of Acquisition}_{ij} &= \{\text{Age}_i \mid \text{Learning instances}_{ij} = c \}\\ \text{Learning instances}_{ij} &= \text{Age}_i \cdot \text{Freq}_j \cdot \text{Exposure}_{ij} \cdot {\color{myred}\text{Cognateness}_{j}}\\ \textbf{where:} \\ c &= 300 \\ \text{Freq}_j &\sim \text{Poisson}(\lambda = 50) \\ {\color{myred}\text{Cognateness}}&{\color{myred}=\text{Levenshtein}(j, j')} \end{aligned} \]

Methods

Barcelona Vocabulary Questionnaire (BVQ)

Participants

Data processing

Modelling approach and statistical inference

Results

Regression coefficients

Figure 4: Posterior distribution of fixed regression coefficients

Marginal effects

Figure 5: Posterior marginal effects

Discussion

Introduction

Experiment 1

N = 112 children (15 longitudinal)

Average age 26.36 months (SD = 4.01, Range = 20.03–32.5)

English monolinguals, Oxford (United Kindgom)

Figure 6: Participant receptive vocabulary sizes across ages and language profiles.

Design

Results

Figure 7: Time course of target fixations in Experiment 1.

Experiment 2

Participants

Stimuli

Procedure

Results (monolinguals)

Figure 8: Time course of target fixations in Experiment 1.

Results (bilinguals)

Figure 9: Time course of target fixations in Experiment 1.

Discussion